package cn.smbms.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.InputStream;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;

public class ImageUtil {
	/**
	 * 生成页面随机验证码
	 * 
	 */
	public String random = "";

	public String getRandom() {
		return random;
	}

	public Color getRandColor(int fc, int bc) {// 给定范围获得随机颜色
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	public BufferedImage creatImage() {
		// 在内存中创建图象
		int width = 60, height = 20;
		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		// 获取图形上下文
		Graphics g = image.getGraphics();
		// 生成随机类
		Random random = new Random();
		// 设定背景色
		g.setColor(getRandColor(200, 250));
		g.fillRect(0, 0, width, height);
		// 设定字体
		g.setFont(new Font("Times New Roman", Font.PLAIN, 18));
		// 画边框
		g.setColor(getRandColor(200, 250));
		g.drawRect(0, 0, width - 1, height - 1);
		// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
		g.setColor(getRandColor(160, 200));
		for (int i = 0; i < 155; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int xl = random.nextInt(12);
			int yl = random.nextInt(12);
			g.drawLine(x, y, x + xl, y + yl);
		}
		// 取随机产生的认证码(4位数字)
		for (int i = 0; i < 4; i++) {
			String rand = String.valueOf(random.nextInt(10));
			this.random += rand;
			// 将认证码显示到图象中
			g.setColor(new Color(20 + random.nextInt(110), 20 + random
					.nextInt(110), 20 + random.nextInt(110)));// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
			g.drawString(rand, 13 * i + 6, 16);
		}
		// 图象生效
		g.dispose();
		return image;
	}

	/**
	 * 实现图像缩放功能
	 */
	public static BufferedImage zoom(InputStream srcFile, int newWidth,	int newHeight) throws Exception {
		// 得到Image对象
		Image img = ImageIO.read(srcFile);
		int height = img.getHeight(null);
		int width = img.getWidth(null);
		// 等比例
        if ( width >= height){   
            newHeight = (int)Math.round((height * newWidth * 1.0 / width));   
        } else {   
            newWidth = (int)Math.round((width * newHeight * 1.0 / height));   
        }
		return zoom(img, newWidth, newHeight);
	}

	public static BufferedImage zoom(String srcFile, int newWidth, int newHeight) {
		// 使用源图像文件名创建对象
		ImageIcon imgIcon = new ImageIcon(srcFile);
		// 得到Image对象
		Image img = imgIcon.getImage();
		int height = img.getHeight(null);
		int width = img.getWidth(null);
		// 等比例
        if ( width >= height){   
            newHeight = (int)Math.round((height * newWidth * 1.0 / width));   
        } else {   
            newWidth = (int)Math.round((width * newHeight * 1.0 / height));   
        }
		return zoom(img, newWidth, newHeight);
	}

	public static BufferedImage zoom(Image srcImage, int newWidth, int newHeight) {
		// 构造预定义的图像类型的BufferedImage对象
		BufferedImage buffImg = new BufferedImage(newWidth, newHeight, BufferedImage.TYPE_INT_RGB);
		// 创建Graphics2D对象，用于在BufferedImage对象上绘图
		Graphics2D g = buffImg.createGraphics();
		// 设置图形上下文的当前颜色为白色
		g.setColor(Color.WHITE);
		// 用图形上下文的当前颜色填充指定的矩形区域
		g.fillRect(0, 0, newWidth, newHeight);
		// 按照缩放的大小在BufferedImage对象上绘制原始图像
		g.drawImage(srcImage, 0, 0, newWidth, newHeight, null);
		// 释放图形上下文使用的系统资源
		g.dispose();
		return buffImg;
	}
	
}
